Sorry if this is a late reply, but HetaOni is a fanmade RPG remake from the game Ao OniIn the game, it starts off the the Main Axis trio + Prussia.I'm ot too great with any explanations so I'll just give off some stater information about it.If you need any indepth information, I can try and answer, or I can suggest a few people.

It's a fanmade rpg game based on Ao Oni which you can see Pewdiepie play on youtube, and if you're interested in Ao Oni and/or Hetalia, you should definitely watch or play Hetaoni, the link for Hetaoni 1 is www.youtube.com/watch?v=509lzL… It's kind of sad and scary, but seriously awesome! It can get confusing at times but bare with it!